
"We found it to be about two-and-a-half times larger than we thought," said analysis team scientist James Farrell of the University of Utah in Salt Lake City. "That's not to say it's getting any bigger. It's just that our ability to see it is getting better."
The size finding, presented at the American Geophysical Union fall meeting in San Francisco last Thursday, has big implications for the extent of the volcano's impact when it next erupts.
The supervolcano underneath the national park last erupted on a massive scale some 640,000 years ago, according to the U.S. Geological Survey (USGS). It is a potential supervolcano, capable of spewing more than 240 cubic miles (1,000 cubic kilometers) of magma across Montana, Idaho, and Wyoming, with global climate effects.
"We believe it will erupt again someday, but we have no idea when," Farrell said.











